The U.S. has asked China to use its leverage with Sudan to push the African nation to allow U.N. peacekeepers into its conflict-ridden Darfur region. China has long supported the Sudanese government, but U.S. Special Envoy for Sudan Andrew Natsios says the Chinese have recently shown a change in attitude, and are now taking an active role in applying pressure on Khartoum. Daniel Schearf reports from Beijing.

China is a long-time political ally of Sudan. As the largest consumer of Sudanese oil and a supplier of arms to the country, China has considerable influence there.

Sudanese President Omar al-Bashir in December appeared to bow to international pressure over the situation in the region of Darfur, where millions have been killed or displaced.

Mr. Bashir promised to allow more U.N. peacekeepers to support struggling African Union forces who are trying to bring peace to the region. But there are concerns he may not fulfill that promise.

Speaking to reporters Friday in Beijing, Andrew Natsios, the U.S. special envoy for Sudan, said had asked the Chinese to use their influence to persuade Mr. Bashir to hold his word.

He said, "Our policy and the Chinese policy are closer than I realized they were, and I think the Chinese are going to play an increasingly important role in helping us to resolve this."

Natsios praised the Chinese for making active efforts to help the peace process in Sudan. Chinese President Hu Jintao, during an African Summit in Beijing last year, urged the Sudanese president to accept U.N. troops.

More than 200,000 people have been killed and millions made homeless in Darfur. Civilians have been murdered and raped by militias allegedly supported by the government in Khartoum.

Natsios said violence in Darfur has worsened since a peace agreement was signed in May. He said the Sudanese government is not providing assistance to displaced people there, and aid agencies are unable to reach those in need.